import { BaseCommand, flags } from '@adonisjs/core/ace'
import type { CommandOptions } from '@adonisjs/core/types/ace'
import db from '@adonisjs/lucid/services/db'
import { Par2Merger } from '#services/par2_merger'

/**
 * The par2 merger's name pass over sets found before it was built (2026-10-23): every set with its file list, newest
 * first, by set row. --dry-run counts what it would merge and shows examples, merging nothing.
 */
export default class ReleasesMergeNames extends BaseCommand {
  static commandName = 'releases:merge-names'
  static description = "Merges releases by their par2 set's file names, for sets found before the name pass; --dry-run shows only"
  static options: CommandOptions = { startApp: true }

  @flags.number({ description: 'Sets to look at (newest first); all without' })
  declare sets: number

  @flags.boolean({ description: 'Count and show, merge nothing' })
  declare dryRun: boolean

  async run() {
    const merger = new Par2Merger()
    // Keyset on (newest created_at, set_id): sets stored in one batch share created_at, and the timestamp stays text
    // so microseconds survive the round trip.
    let before = ['9999-12-31', '']
    let looked = 0
    let merges = 0
    let releases = 0
    const examples: string[] = []
    while (this.sets === undefined || looked < this.sets) {
      const { rows } = await db.rawQuery(
        `SELECT set_id, at::text AS at FROM (
           SELECT s.set_id, max(s.created_at) AS at FROM par2_sets s WHERE EXISTS (SELECT 1 FROM par2_files f WHERE f.set_id = s.set_id)
           GROUP BY s.set_id) x
         WHERE (at, set_id) < (?::timestamptz, ?) ORDER BY at DESC, set_id DESC LIMIT ${this.dryRun ? 50 : 500}`,
        before
      )
      if (rows.length === 0) break
      for (const { set_id: setId } of rows) {
        looked++
        if (this.dryRun) {
          const found = await db.transaction(async (trx) => merger.nameMatches(trx, setId.trim()))
          if (found) {
            merges++
            releases += found.size
            if (examples.length < 15) {
              const { rows: names } = await db.rawQuery(`SELECT id, name, files FROM releases WHERE id = ANY(?) ORDER BY id`, [[...found.keys()]])
              examples.push(names.map((n: any) => `${n.name.slice(0, 50)} [${n.files}]`).join(' + '))
            }
          }
        } else {
          const merged = await merger.mergeByName(setId.trim())
          if (merged > 0) {
            merges++
            releases += merged + 1
          }
        }
      }
      before = [rows.at(-1).at, rows.at(-1).set_id]
      if (this.dryRun || looked % 20_000 < 500) this.logger.info(`${looked} sets looked at: ${releases} releases ${this.dryRun ? 'would merge' : 'merged'} into ${merges}.`)
    }
    this.logger.info(`Done: ${looked} sets looked at, ${releases} releases ${this.dryRun ? 'would merge' : 'merged'} into ${merges}.`)
    for (const e of examples) this.logger.info(`  ${e.slice(0, 300)}`)
  }
}